US President George W Bush is under pressure from Democrats to reveal if he was behind the leaking of Iraq secrets.

Court papers cite an ex-official as saying he had been told he had Mr Bush's authorisation to discuss classified material with journalists.

The White House says any information released was done "in the public interest", arguing the president has the power to declassify information.

The ex-official, Lewis Libby, is facing trial in a separate CIA leak case.

He is accused of obstructing an investigation into the leaking of a CIA agent's identity.

Mr Bush - who is not accused of authorising the release of the agent's name - has in the past condemned leaks and has said he would sack anyone involved.

The president's supporters say even if Mr Libby's testimony is accurate, what the president is alleged to have done does not constitute a leak because Mr Bush had the authority to release the information.

But the BBC's Justin Webb in Washington says President Bush is once again fighting for his political credibility, with Democrats smelling blood.

'Breathtaking disclosure'

Mr Libby said he was told in July 2003, when he was chief-of-staff to Vice-President Dick Cheney, to give a reporter pre-war intelligence, court papers reveal.